H
Harrington
Guest
It looks like my FD has lasted longer than the failure list.
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BMW Final Drive Failure Form
- Thread starter PPARKER1024
- Start date
From my feeble memory Paul Glaves wrote an article in his "Bench Wrenching" series in the ON about this.
The main problem is NOT a design flaw but an assembly flaw. The bearing preload is to high and this causes the ball bearing to fail. IF this was a design issue there would be a lot more than the estimated 4% of the bikes having failures. Failures would also be higher from people riding 2-up, pulling trailers, etc.
On a side note, does anyone of these statistics track how many of the failures where second or third failures on the same bike because the owner or dealer just replaced the failed bearing and did NOT check the bearing preload. Talk on the LT site is this is also a very large number.
Yes BMW has problems, doesn't HD, Honda, Yamaha, etc.. Difference may be that the Japanese will admit they have a problem, German pride won't.
Roy
The main problem is NOT a design flaw but an assembly flaw. The bearing preload is to high and this causes the ball bearing to fail. IF this was a design issue there would be a lot more than the estimated 4% of the bikes having failures. Failures would also be higher from people riding 2-up, pulling trailers, etc.
On a side note, does anyone of these statistics track how many of the failures where second or third failures on the same bike because the owner or dealer just replaced the failed bearing and did NOT check the bearing preload. Talk on the LT site is this is also a very large number.
Yes BMW has problems, doesn't HD, Honda, Yamaha, etc.. Difference may be that the Japanese will admit they have a problem, German pride won't.
Roy
Maybe a little different, but regarding the Japanese admitting a problem; it sure took Toyota several years to fess up and then there was a lot of denial. As to the Germans; they'll never admit a fault. I just retired from a Swiss company and they had the same characteristic.
deilenberger
A bozo on the bus
Roy - this depends on which rear drive you're talking about.
- Airhead drives - the wheel/hub splines went bad. Pretty much a matter of time. Businesses sprang up to rebuild these splines.
- Klassic-K bikes with monolever drive - the input shaft splines go bad (that's just a matter of time, you can slow it down, but due to the design geometry you can't prevent it..) The same businesses who rebuilt airhead splines now rebuild klassic-k splines.
- Oilheads and later K bikes - these are the ones you're discussing. This was an assembly problem, causing the bearings to gall and fail. There are a few noteable rebuilders who have a very good reputation for an almost non-existent return failure rate - meaning it can be done right, just the factory (actually Getrag I believe) didn't bother.
- Hexheads and current K bikes - these were primarily an environmental problem with the "lifetime lubrication".. once BMW went to a 600 mile change of the fluid, the number of drives failing precipitously dropped. They also adopted a 12k service interval for the drive fluid, and this also seems to be helping. It's actually rather rare to hear of one failing now, expecially the ones made since 2007 when the 600 mile service was introduced. FWIW - these do not have a "preload" bearing design. One end of the hub is supported in a needle bearing (allowing axial movement) - the other end in an externally mounted and sealed ball bearing.
So - it all depends on what'cha talking about. And not much new under the sun. Peter Nettersheim discussed rear drive problems with pre-war bikes at one time.
Well, just because earlier bikes had issues does not excuse final drive failures at low mileages or inane interviews with executives who may be in a position to do something about it. Next time there is a survey, why doesn't the BMW leadership ask if the members would like MOA to advocate for them with BMW on issues such as premature mechanical failures or other important issues?
cjack
K Bikes Complex by Choice
As to the latest drives, it seemed to me that the early failures were seal problems mostly, loose splines on the wheel carrier, and some input needle bearing failures.
The change in the drain interval, may have resulted from some form of the seal failures and maybe the input bearing issues. The loose splines had to be a QC issue as well as some of the seal failures (seal lip turned over or some such thing...very early). In addition to the drain interval changes, the fluid quantity was changed too. This had to do with possibly increased pressure in the drive causing a wear mark on the surface where the seal rides.
There have been some big bearing failures...this bearing is a sealed bearing and does not reside inside the drive any longer and does not share the oil bath.
While the drive failures get the most press, I am more concerned with the random timing chain failures. Mostly on the transverse K1200 but then the K1300 is newer and lower mileage. I am concerned when a couple of my personal riding friends have had the failure. I notice that the new S1000RR and the K1600 have a different cam change arrangement. There is also a new chain guard for the K1300 and I guess the K1200 bikes which helps to prevent the chain from jumping a tooth.
While a major engine failure is not considered safety related, I am dissapointed if BMW doesn't step right up in the case of a chain failure in or out of warranty.
I do remember an interview in the ON with a high ranking BMW individual, and while his personal story is interesting, I couldn't get the quality control issues out of my mind when I was reading. I don't think a direct question about cam chains or final drives would ever get answered nor is it in good taste to publish that sort of a confrontation, but I wish I didn't have to think about it at all.
BMW is still the best...I think...
The change in the drain interval, may have resulted from some form of the seal failures and maybe the input bearing issues. The loose splines had to be a QC issue as well as some of the seal failures (seal lip turned over or some such thing...very early). In addition to the drain interval changes, the fluid quantity was changed too. This had to do with possibly increased pressure in the drive causing a wear mark on the surface where the seal rides.
There have been some big bearing failures...this bearing is a sealed bearing and does not reside inside the drive any longer and does not share the oil bath.
While the drive failures get the most press, I am more concerned with the random timing chain failures. Mostly on the transverse K1200 but then the K1300 is newer and lower mileage. I am concerned when a couple of my personal riding friends have had the failure. I notice that the new S1000RR and the K1600 have a different cam change arrangement. There is also a new chain guard for the K1300 and I guess the K1200 bikes which helps to prevent the chain from jumping a tooth.
While a major engine failure is not considered safety related, I am dissapointed if BMW doesn't step right up in the case of a chain failure in or out of warranty.
I do remember an interview in the ON with a high ranking BMW individual, and while his personal story is interesting, I couldn't get the quality control issues out of my mind when I was reading. I don't think a direct question about cam chains or final drives would ever get answered nor is it in good taste to publish that sort of a confrontation, but I wish I didn't have to think about it at all.
BMW is still the best...I think...
cjack
K Bikes Complex by Choice
As to the latest drives, it seemed to me that the early failures were seal problems mostly, loose splines on the wheel carrier, and some input needle bearing failures.
The change in the drain interval, may have resulted from some form of the seal failures and maybe the input bearing issues. The loose splines had to be a QC issue as well as some of the seal failures (seal lip turned over or some such thing...very early). In addition to the drain interval changes, the fluid quantity was changed too. This had to do with possibly increased pressure in the drive causing a wear mark on the surface where the seal rides.
There have been some big bearing failures...this bearing is a sealed bearing and does not reside inside the drive any longer and does not share the oil bath.
While the drive failures get the most press, I am more concerned with the random timing chain failures. Mostly on the transverse K1200 but then the K1300 is newer and lower mileage. I am concerned when a couple of my personal riding friends have had the failure. I notice that the new S1000RR and the K1600 have a different cam change arrangement. There is also a new chain guard for the K1300 and I guess the K1200 bikes which helps to prevent the chain from jumping a tooth.
While a major engine failure is not considered safety related, I am disappointed if BMW doesn't step right up in the case of a chain failure in or out of warranty.
I do remember an interview in the ON with a high ranking BMW individual, and while his personal story is interesting, I couldn't get the quality control issues out of my mind when I was reading. I don't think a direct question about cam chains or final drives would ever get answered nor is it in good taste to publish that sort of a confrontation, but I wish I didn't have to think about it at all.
BMW is still the best...I think...
The change in the drain interval, may have resulted from some form of the seal failures and maybe the input bearing issues. The loose splines had to be a QC issue as well as some of the seal failures (seal lip turned over or some such thing...very early). In addition to the drain interval changes, the fluid quantity was changed too. This had to do with possibly increased pressure in the drive causing a wear mark on the surface where the seal rides.
There have been some big bearing failures...this bearing is a sealed bearing and does not reside inside the drive any longer and does not share the oil bath.
While the drive failures get the most press, I am more concerned with the random timing chain failures. Mostly on the transverse K1200 but then the K1300 is newer and lower mileage. I am concerned when a couple of my personal riding friends have had the failure. I notice that the new S1000RR and the K1600 have a different cam change arrangement. There is also a new chain guard for the K1300 and I guess the K1200 bikes which helps to prevent the chain from jumping a tooth.
While a major engine failure is not considered safety related, I am disappointed if BMW doesn't step right up in the case of a chain failure in or out of warranty.
I do remember an interview in the ON with a high ranking BMW individual, and while his personal story is interesting, I couldn't get the quality control issues out of my mind when I was reading. I don't think a direct question about cam chains or final drives would ever get answered nor is it in good taste to publish that sort of a confrontation, but I wish I didn't have to think about it at all.
BMW is still the best...I think...
